In many arts, and especially in the textile industry, it is necessary to change one or more colors in an original pattern. In the textile industry, for example, the following problem is presented:
Given a swatch of material of a certain geometric design and color combination, is there a simple, quick and economically viable means by which a fabric user or designer can explore and specify other color variations of that particular geometric design?
The fabric industry currently solves this problem in a variety of ways, all of which introduce costly delays that the end user would like to eliminate. According to one procedure, a handwoven sample is made by a mill for submission to a clothing manufacturer. A reason for this practice derives from the fact that in the production of designs for woven fabrics no accurate idea of the appearance of the finished fabric can be obtained from drawings or paintings, except such as reproduce with enormous labor the most minute details of the textile. So great would the labor be in the production of adequate drawings and paintings that in practice another accepted procedure has been, once the weaving scheme is decided on, to set up a loom for the production of a number of color combinations from which are selected those which seem most suitable for the purpose for which the cloth is to be used. Alternatively, the manufacturer notifies the mill of the desired colors and the mill then hand-weaves another sample. This is also costly, as well as time consuming. Moreover, it is often found that the colors selected by the manufacturer, when woven in the original pattern, do not produce the desired aesthetic effect. It is then necessary to repeat the entire process.
It has been proposed to take a separate photographic negative of each of all the parts of a basic design and produce positive transparencies from the negatives, project beams of light through the several positives so as to reproduce the configuration of the basic design, and color the individual beams, varying their individual colors at will until the reproduced design has a desired appearance. U.S. Pat. Nos. 1,657,415 (Smith) and 1,788,135 (Twyman et al) describe such a scheme. In Twyman et al it is proposed to weave a fabric from threads of red, green and blue, these colors being so selected that they can be photographed through filters which would suppress in turn any two of the three colors. This scheme has the inherent problem of registration.